This patent application includes a claim of foreign priority to prior filed Japanese Patent Application 2001-270684 filed Sep. 6, 2001.
The present invention relates to a protective guide used for machine tools, electric equipments, industrial robots, transportation machines and the like, for safely and reliably protecting and guiding flexible cables and the like such as electric wire cables, optical fiber cables, liquid supply hoses and the like.
When an electric wire cable or a hydraulic or pneumatic pressure hose is connected to a machine tool, an earthmover, or a moving equipment such as a transportation equipment and the like, undue torsion or tension is generated in the cable or hose during movement so that the cable or hose is damaged and an outward appearance becomes irregular. Thus, various protective guides for supporting and guiding these cables or hoses have been provided.
A movable guide equipment for cables or the like proposed in, for example, Japanese Patent Laid-Open Publication No. Hei. 10-28310 is one integrally molded as a whole and made of plastics as described in the publication (the reference numerals of the members are the same as in the publication below). In the movable guide equipment, at least one row of protruded pieces (8) is integrally molded on a bottom surface of a bottom wall (2) in an accommodation member (1), which receives the cables or the like, the protruded pieces divided at a bend portion R in the accommodation member (1) are brought into contact with each other so that a fixed bend position can be, and a lid piece (11) is integrally molded on an upper end portion of one side wall piece (3) in the accommodation member (1) so as to be openable and the lid piece is detachably provided on the other side wall piece (3).
Further, in an energy conductor holding device proposed in Japanese Examined Patent Publication No. Sho. 62-15008, a plastic small diameter tube member is disposed inside, a fan-shaped groove is provided in an up and down direction on an outer peripheral surface of the side portion, half bodies of a tubular member of a metallic plate are provided on upper and lower portions on the outside and the half bodies of the tubular member are attached by engaging them with a pin so that the small diameter member is sandwiched by the half bodies from the up and down directions. Thus, the energy conductor holding device includes so called a connection link structure, in which a connection of the holding device in a longitudinal direction is performed by the engagement between the groove of the inside small diameter tube member and the upper and lower tubular member half bodies.
The movable guide equipment for the cables and the like in the former publication Japanese Patent Laid-Open Publication No. Hei. 10-28310 is integrally molded as a whole and made of plastics having flexibility. Thus, when a large load is acted on the bend portion of the equipment from above, the movable guide equipment is buckled so that a correct bending radius cannot be maintained. Further, since the movable guide equipment is made of flexible material it is liable to flex and cannot receive or support a heavier object to be supported. Thus, when weight is applied on one side of the equipment, the movable guide equipment becomes unstable and is twisted. If a straight portion of the equipment is long, there was a problem that flexure is large so that a bend portion of the equipment can fall down due to the shortage of rigidity.
Further, in the energy conductor holding device of the latter publication half bodies of the upper and lower tubular members are produced by the use of a metallic material and a small diameter member is molded of synthetic resin. Thus, the metallic material shaves the synthetic resin material during the sliding of the half bodies of the upper and lower tubular members and the small diameter member, to produce much worn powder. Further, since the equipment also uses a metallic material it becomes heavier as compared with equipment molded of only synthetic resin and additionally, since a metallic material portion and a synthetic resin portion are collided with each other during the movement of a supporting device, a large noise is generated. Further, since the half bodies of the most peripheral upper and lower tubular members are made of metal there was a problem that noise generated when the upper frame hits a floor surface during their movement is large.
Problems to be solved. To provide a protective guide for cables and the like, which can prevent undue bending or running off of the cable and the like whereby it can be reliably received and protected, and at the same time which can attain smooth movement guide of the cable and the like by suppressing contact worn powder, which is liable to be produced by bending and torsion, and further, whose assembling and maintenance is simple and whose noise is small and which is lightweight and is inexpensive.
Accordingly, an object of the present invention is to solve the above-mentioned prior art problems and to provide a protective guide for cables and the like, which can prevent undue bending or running off of the cable and the like whereby it can be reliably received and protected, and at the same time which can attain smooth movement guide of the cable and the like by suppressing contact worn powder, which is liable to be produced by bending and torsion, and further, whose assembling and maintenance are simple and whose noise is small and which is lightweight and is inexpensive.
To solve the above-mentioned problems in a protective guide for cables and the like, which is an invention of claim 1, a flexible tube connected between a movable end portion of the cable and a fixed end portion of the cable and incorporating cables and the like includes a bellows-shaped tubular peripheral wall, and a large number of bending-limiting units surrounded by and fitted onto the bellows-shaped tubular peripheral wall of said flexible tube at desired intervals includes bending-holding portions, which hold a required bending position of said flexible tube while abutting with each other on a bending inner peripheral side, and bending-suppressing portions, which hold a linearly extended position of said flexible tube while abutting with each other on a bending outer peripheral side.
In a protective guide for cables and the like, which is the invention of claim 2, in addition to the configuration of claim 1, said flexible tube and said bending-limiting units are formed of resin thereby to solve said problems.
In a protective guide for cables and the like, which is the invention of claim 3, in addition to the configuration of claim 1 or 2, the bellows-shaped tubular peripheral wall of said flexible tube includes fine bellows portions formed on said bending inner peripheral side and rough bellows portions formed on said bending outer peripheral side thereby to solve said problems.
In a protective guide for cables and the like, which is the invention of claims 4 or 6, in addition to the configuration of any one of claims 1 to 3, each of said bending-limiting unit has a frame structure of a rectangular section thereby to further solve the problems.
In a protective guide for cables and the like, which is the invention of claims 5, 7 and 8 in addition to the configuration of claims 1 to 4, said bending-limiting unit is formed by detachably engaging an attachment disposed on the bending inner peripheral side of said flexible tube and a clip disposed on the bending outer peripheral side of said flexible tube thereby to further solve the problems.
If the flexible tube including a bellows-shaped tubular peripheral wall used in the present invention has a shape that can be appropriately bend while incorporating cables and the like it may have any shape such as a circular section, an oval section, a rectangular section or the like.
If a position of forming the bending holding portion in said bending-limiting unit is one where the adjacent bending holding portions are sequentially abutted with each other in a plane of a bend portion in said flexible tube and can maintain a required bend position of said flexible tube, any position on the bend inner peripheral side may be used. Further, if a position of forming the bend suppressing portion of said bending-limiting unit is one where the adjacent bending holding portions are sequentially abutted with each other in a plane of a bend portion in said flexible tube and can maintain a linearly extended position of said flexible tube, any position on the bend outer peripheral side may be used.
When cables and the like, which perform power supply, liquid supply or the like to moving machines such as machine tools, electric devices, industrial robots, transportation machines or the like or to a moving portion in a machine, are moved together with the moving portion of the machine, the protective guide of the cables and the like, which are the present invention, sequentially displace a portion where a flexible tube shows a required bend position in accordance with the movement position of a movable end portion of the cable while ensuring a required bending radius which is formed by mutually adjoining the bending holding positions of a large number of fitted bending-limiting units surrounded by the flexible tube. Further, bending suppressing portions in the large number of bending-limiting units, which were surrounded by and fitted onto the rest of said flexible tube are mutually adjoined with each other and protect collected cables and the like while keeping a linearly extended position.